Bicycles, particularly those such as road racers with drop handles, are known to be equipped with brake and shift operation devices, which are brake operation devices to which shift operation functions are added (for instance, see Japanese Patent Laid-Open No. 2-225191). A conventional brake and shift operation device comprises: a brake bracket, a lever member pivotally mounted on the brake bracket, and a shift operation mechanism provided on the lever member. In this brake and shift operation device, the lever member comprises: a pivot support portion pivotally mounted around a first axis to the brake bracket, a lever body pivotally mounted around a second axis which differs from the first axis to the pivot support portion, and a shift operation mechanism capable of performing shift operation by pivoting of the lever body around the second axis. In the conventional brake and shift operation device, brake operation is performed by pivoting the lever member including the lever body around the first axis, and shift operation is performed by pivoting the lever body around the second axis.
In brake and shift operation devices of this type, there are those with lever members provided with rotational position sensors that detect positions of rotational movement of a cable winding device provided in the shift operation mechanism to display shift positions of the shift device. Output from this rotational position sensor enables shift positions to be electrically displayed on a shift position display device provided, for instance, on a handle bar.
Since the above-described conventional configuration is capable of displaying shift positions by means of electric signals from the rotational position sensor, display position is not limited, and shift positions can be displayed at a position that is easily viewable from a rider. However, because the conventional configuration is premised on a shift position display device (so-called cycle computer) to be provided by the rider, shift positions could not be displayed unless relatively expensive cycle computers were provided.
The object of the current invention is to enable, in an inexpensive manner, displaying of shift positions with a brake and shift operation device mounted on a drop handle.